SAO was okay in the first season, even the second season, but then it became a bit like *The New Gate* (which I've read).
It seems novel but then if you've seen like dozens of books with a "virtual world" premise, "transported to another world" premise, or other such premise, then it looks a bit plain, especially when other titles have gone way past it to add their own flavors to the idea.
I think people underestimate just how many of these books there are.
I wouldn't really say it's bad but it is also frankly over-rated compared to what the show actually offers. Also, I think it's interesting to see new characters and new ideas, not seeing Kirito go off onto another map.
While No Game No Life also had characters who entered random games, and were immediately geniuses at it, the show was also pretty clearly a parody.
Also, Kirito himself doesn't have that much of a personality / backstory. He's a fairly plain character. In other titles, the characters are fleshed out more.